Conscious Brain-to-Brain Communication in Humans Using Non-Invasive Technologies

Human sensory and motor systems provide the natural means for the exchange of information between individuals, and, hence, the basis for human civilization. The recent development of brain-computer interfaces (BCI) has provided an important element for the creation of brain-to-brain communication systems, and precise brain stimulation techniques are now available for the realization of non-invasive computer-brain interfaces (CBI). These technologies, BCI and CBI, can be combined to realize the vision of non-invasive, computer-mediated brain-to-brain (B2B) communication between subjects (hyperinteraction). Here we demonstrate the conscious transmission of information between human brains through the intact scalp and without intervention of motor or peripheral sensory systems. Pseudo-random binary streams encoding words were transmitted between the minds of emitter and receiver subjects separated by great distances, representing the realization of the first human brain-to-brain interface. In a series of experiments, we established internet-mediated B2B communication by combining a BCI based on voluntary motor imagery-controlled electroencephalographic (EEG) changes with a CBI inducing the conscious perception of phosphenes (light flashes) through neuronavigated, robotized transcranial magnetic stimulation (TMS), with special care taken to block sensory (tactile, visual or auditory) cues. Our results provide a critical proof-of-principle demonstration for the development of conscious B2B communication technologies. More fully developed, related implementations will open new research venues in cognitive, social and clinical neuroscience and the scientific study of consciousness. We envision that hyperinteraction technologies will eventually have a profound impact on the social structure of our civilization and raise important ethical issues.     

A host-vector system for gene cloning in the cyanobacterium Synechocystis PCC 6803

Summary Synechocystis 6803 contains at least four cryptic plasmids of 2.27 kb (pUS1, pUS2 and pUS3) and 5.20 kb (pUS4). The 1.70 kb HpaI fragments of the related plasmids pUS2 and pUS3 were cloned into the Ap^r gene of the E. coli plasmid pACYC177, yielding the Km^r hybrid plasmids pUF12 and pUF3 respectively. pUF3 recombines in Synechocystis 6803 with a 2.27 kb plasmid giving the Km^r shuttle vector pUF311. The 1.35 kb HaeII fragment containing the Cm² gene of the E. coli plasmid pACYC184 was cloned in pUF311 generating the Cm^r Km^r shuttle vector pFCLV7. Wild-type cells of Synechocystis 6803 are transformed, albeit poorly, by the plasmids pUF3, pUF12 and pFCLV7. pFCLV7 very efficiently transforms the SUF311 strain of Synechocystis 6803 containing pUF311 as a resident plasmid. This is due to recombination between the homologous parts of pFCLV7 and pUF311. For the same reason the strain SUF311 is also efficiently transformable by E. coli plasmids, as shown for pLF8, provided that they have some homology with the E. coli part of pUF311.The combined use of Synechocystis 6803 strain SUF311 and of plasmids pFCLV7 and pLF8 generates an efficient host-vector system for gene cloning in this facultatively heterotrophic cyanobacterium.     

Major Central Nervous System Myelin Glycoprotein of the African Lungfish (Protopterus dolloi) Cross-Reacts with Myelin Proteolipid Protein Antibodies, Indicating a Close Phylogenetic Relationship with Amphibians

CNS myelin was isolated from the spinal cord of the African lungfish Protopterus dolloi. Its proteins consisted of (1) two basic proteins (16,000 and 18,500 apparent Mr) that reacted with anti-human CNS myelin basic protein antibodies and (2) a major protein (29,000 apparent Mr) that stained with concanavalin A-horseradish peroxidase and bound to anti-rat CNS myelin proteolipid protein (PLP) antibodies. This dominant 29,000 Mr protein showed no reaction with antibodies against the major bovine PNS myelin glycoprotein P0. Following treatment with endoglycosidase F the 29,000 Mr protein was reduced in size to a 26,000 apparent Mr component that no longer bound concanavalin A but retained the anti-PLP reactivity. These results agree with a concanavalin A-binding oligosaccharide linked through asparagine to a protein backbone of PLP homology. The major 29,000 Mr lungfish CNS myelin protein was therefore termed g-PLP (glycosylated proteolipid protein). This is the first report demonstrating the occurrence of a PLP-cross-reactive protein in CNS myelin of a fish. It attests to the close phylogenetic relationship of lungfishes to amphibians. Amphibians were previously recognized as the oldest class bearing PLP in its CNS myelin.     

Transgenic Analysis of a PotentialHoxd-11Limb Regulatory Element Present in Tetrapods and Fish

Genes of theHoxDcomplex related to theDrosophila Abd-Bgene are involved in the morphogenesis of vertebrate paired appendages.Hoxd-11,for instance, is necessary in combination with otherHoxgenes for the proper development of different parts of the tetrapod limbs. Sequence comparisons between the mouse, chicken, and zebrafishHoxd-11loci have revealed the conservation of several blocks of DNA sequence which may be of importance for the regulation ofHoxd-11expression. We have used transgenic mice to show that one of these conserved elements specifically drives expression in a proximal-posterior part of developing forelimbs. Production of mice transgenic for a full fishHoxd-11construct as well as for mouse–fishHoxd-11chimeric constructs shows that the fish counterpart of this sequence is able to elicit expression in mouse forelimbs as well, though in a slightly different domain. However, this fish element requires the presence of the mouse promoter and does not work in its own context. These results are discussed in light of both the control ofHoxdgene expression during limb development and the use of a comparative interspecies approach to understand the regulation of genes involved in vertebrate development.     

The potato StMKK5-StSIPK module enhances resistance to Phytophthora pathogens through activating the salicylic acid and ethylene signalling pathways

Mitogen-activated protein kinase (MAPK) cascades play pivotal roles in plant responses to both biotic and abiotic stress. A screen of a Nicotiana benthamiana cDNA virus-induced gene silencing (VIGS) library for altered plant responses to inoculation with Phytophthora infestans previously identified an NbMKK gene, encoding a clade D MAPKK that we renamed as NbMKK5, which is involved in immunity to P. infestans. To study the role of the potato orthologous gene, referred to as StMKK5, in the response to P. infestans, we transiently overexpressed StMKK5 in N. benthamiana and observed that cell death occurred at 2 days postinfiltration. Silencing of the highly conserved eukaryotic protein SGT1 delayed the StMKK5-induced cell death, whereas silencing of the MAPK-encoding gene NbSIPK completely abolished the cell death response. Further investigations showed that StMKK5 interacts with, and directly phosphorylates, StSIPK. Furthermore, both StMKK5 and StSIPK trigger salicylic acid (SA)- and ethylene (Eth)-related gene expression, and co-expression of the salicylate hydroxylase NahG with the negative regulator of Eth signalling CTR1 hampers StSIPK-triggered cell death. This observation indicates that the cell death triggered by StMKK5-StSIPK is dependent on the combination of SA- and Eth-signalling. By introducing point mutations, we showed that the kinase activity of both StMKK5 and StSIPK is required for triggering cell death. Genetic analysis showed that StMKK5 depends on StSIPK to trigger plant resistance. Thus, our results define a potato StMKK5-SIPK module that positively regulates immunity to P. infestans via activation of both the SA and Eth signalling pathways.     

Identification and characterization of adhesive factors of Clostridium difficile involved in adhesion to human colonic enterocyte-like Caco-2 and mucus-secreting HT29 cells in culture

Experiments reported in this communication showed that the highly toxinogenic Cd 79685, Cd 4784, and Wilkins Clostridium difficile strains and the moderately toxinogenic FD strain grown in the presence of blood adhere to polarized monolayers of two cultured human intestinal cell lines: the human colonic epithelial Caco-2 cells and the human mucus-secreting HT29-MTX cells. Scanning electron microscopy revealed that the bacteria interacted with well-defined apical microvilli of differentiated Caco-2 cells and that the bacteria strongly bind to the mucus layer that entirely covers the surface of the HT29-MTX cells. The binding of C. difficile to Caco-2 cells developed in parallel with the differentiation features of the Caco-2 cells, suggesting that the protein(s) which constitute C. difficile-binding sites are differentiation-related brush border protein(s). To better define this interaction, we tentatively characterized the mechanism(s) of adhesion of C. difficile with adherence assays. It was shown that heating of C. difficile grown in the presence of blood enhanced the bacterial interaction with the brush border of the enterocyte-like Caco-2 cells and the human mucus-secreting HT29-MTX cells. A labile surface-associated component was involved in C. difficile adhesion since washes of C. difficile grown in the presence of blood without heat shock decreased adhesion. After heating, washes of C. difficile grown in the presence of blood did not modify adhesion. Analysis of surface-associated proteins of C. difficile subjected to different culture conditions was con-ducted. After growth of C. difficile Cd 79685, Cd 4784, FD and Wilkins strains in the presence of blood and heating, two predominant SDS-extractable proteins with molecular masses of 12 and 27 kDa were observed and two other proteins with masses of 48 and 31 kDa disappeared. Direct involvement of the 12 and 27 kDa surface-associated proteins in the adhe-sion of C. difficile strains was demonstrated by using rat polycolonal antibodies pAb 12 and pAb 27 directed against the 12 and 27kDa proteins. Indeed, adhesion to Caco-2 cell monoiayers of C. difficiie strains grown in the presence of blood, without or with heat-shock, was blocked. Taken together, our results suggest that C. difficiie may utilize blood components as adhesins to adhere to human intestinal cultured cells.     

Density distribution of 2′,3′-cyclic nucleotide 3′-phosphodiesterase and myelin proteins in particulate material from myelin deficient (mld) mutant and control brains

Total particulate material from control and myelin deficient (mld) brains was subjected to density centrifugation on a continuous sucrose gradient. Particles from control brains distributed in a bell-shaped mode with a peak density near 0.64 M-sucrose. In mld material only a slight elevation of optical density was observed near 0.8 M-sucrose. The highest specific activities of 2′,3′-cyclic nucleotide 3′-phosphodiesterase were observed at densities of 0.63 and 0.71 M-sucrose for mld and control brains, respectively. The peak of myelin basic protein in control fractions was near 0.60 M-sucrose. In mld fractions no peak was observed. Proteolipid and Wolfgram proteins had a maximum near 0.65 and 0.73 M-sucrose in control and mld fractions, respectively. The absence of myelin basic proteins in all the fractions makes it unlikely that, in mld mice, myelin basic proteins are synthesized but not incorporated into myelin.     

Distribution of lipid synthesizing enzymes, 2′,3′-cyclic nucleotide 3′-phosphodiesterase,and myelin proteins in rat forebrain subfractions during development

The distribution of UDP-galactose: ceramide galactosyltransferase (CGalT) was studied in subcellular fractions of rat forebrain during development using zonal centrifugation on linear gradients. Specialized subfractions: SN 1, a microsomal fraction, SN 4, a myelin-related fraction, and purified myelin were also used for this study. For comparison, two microsomal lipid synthesizing enzymes, a myelin-specific enzyme, 2,3-cyclic nucleotide 3-phosphodiesterase and myelin proteins were measured in the same subfractions. UDP-glucose: ceramide glucosyltransferase and cerebroside sulfotransferase were confined to microsomes. CGalT was ferase and cerebroside sulfotransferase were confined to microsomes. CGalT was localized in microsomes, but also in myelin and myelin-related fractions. The developmental change in distribution of CGalT in adult animals toward myelin containing fractions could indicate that the replacement of galactosylceramide in compact myelin could be carried out in close proximity to compact myelin (mesaxon, paranodal loops) rather than in the distant oligodendrocyte perikaryon.